Conventionally, for example in a copying machine, there is installed a paper feeding device for feeding copy paper which is provided with a plurality of paper feed cassettes classified by each size of copy paper. For conveying the copy paper from the paper feeding device, lateral feed where the transport direction coincides with the crosswise direction of the copy paper, is preferred in terms of transport speed to longitudinal feed where the transport direction coincides with the lengthwise direction of the copy paper, and therefore in some of the copying machines, even large size copy paper such as size B4 or A3 is fed thereto by lateral feed.
However, feeding large sized copy paper laterally causes the photosensitive drum, the transport rollers, the transport paths of the copy paper, and other parts inside the copying machine to become large. As a result, the copying machine itself becomes large and bulky, and its cost rises. Hence generally, the method of longitudinally feeding copy paper of a large size such as A3 or B4, and laterally feeding copy paper of a size not larger than A4, is adopted.
However, with such an arrangement, in a copying machine with a variable magnification function that performs reductions and enlargements, for instance B5R and A4R, paper feeding cassettes that feed the copy paper longitudinally are necessary to perform reduced copies. In addition, when thinking of transport speed, A4 and B5 paper feeding cassettes that feed the copy paper laterally, are also necessary. Accordingly, when it comes to installing those different types of paper feeding cassettes, either the paper feeding device has to be designed in a large size, or the paper feeding cassettes must be changed as occasion calls. This causes the size of the copying machine to be large and its cost to rise, or the operation of the copying machine becomes complicated.
Therefore, copying machines designed to solve the above problems have been disclosed in Japanese Patent Publication (laid-open) No. 59245/1981 and No. 123859/1984 (Tokukaisho 56-59245 and 59-123859), wherein the same paper feeding cassette is commonly used, for example, for both B5 and B5R copy paper or for A4 and A4R copy paper, and by rotating the feeding position of copy paper in the paper feeding cassette, the arrangement permits the copy paper to be shifted to either a lateral or longitudinal feeding position.
In the conventional apparatus of this type, when copy paper in a cassette has been consumed during its feeding operation of, for example, A4 copy paper, it is necessary to stop the copying operation for a while and then, if there are any other paper feeding cassettes available to feed A4 copy paper, it is necessary to start the operation again after having switched the paper feeding cassette to one of those cassettes available.
However, in the conventional arrangement, in order to start the copying operation again when the copy paper has been consumed, before turning on the print switch again, the operator has to perform operations such as; supply copy paper, select a proper paper feeding cassette if there are any fixed or rotatable cassettes storing copy paper of the same size in the same feeding position, or rotate copy paper in a rotatable cassette so as to be set in the same feeding position by operating a rotation key if there are any rotatable cassettes storing copy paper of the same size but set in a different feeding position. Accordingly, the arrangement presents problems in that it is difficult to obtain an efficient operability, and as a result, time required for the copying machine to convey a given amount of copy paper tends to increase.